This invention relates to an apparatus for closing a fireproof door in case of emergency.
In the prior closing apparatus, a straight arm is interconnected between a driving shaft of a door closer secured to a fireproof door and a slider slidably mounted inside a release secured to a door frame. The sliding movement of the slider is prevented by a latch mechanism, which is arranged inside the release and operated by a solenoid, for maintaining the firepoof door in its open position against a closing force of door closer. When the fireproof door must be closed in case of emergency such as fire, a solenoid is electrized to operate the latch mechanism to release the slider so as to be slid by the closing force of the door closer to close the fireproofdoor.
With the above prior apparatus, however, opening angle of the fireproof door is limited to less than 130.degree. as an arm interconnecting the door closer and the slider is the single and straight one. Thus, it is not able to be utilized for fireproof doors, the opening angle of which is over 130.degree..